Python Errors and Exceptions

1. python中的try{}catch{}

2. raise exception

3. try...except ... else.. 

4. finally块 

1. python中的try{}catch{}

python中的异常处理的关键字和c#中的是不相同的，python中使用try，except关键在来处理异常，如下：

def dive(x, y):

    try:

        result = x / y;

    except ZeroDivisionError as z :

            print("division by zero.", z);

    else:

        print("the result is ", result);

    finally:

        print("executing finally caluse.");

 

2. raise excepption

python中如果在except中如果需要将异常重新抛出可以使用关键字raise，类似于c#中的throw关键字。

def raise_test():

    try:

        result = 1 / 0;

    except ZeroDivisionError :

        print ("can not process the exception, to throw ...");

        raise;

    finally:

        print("in finally block");

	raise_test(); 

3. try...except ... else..

 

It is useful for code that must be executed if the try clause does not raise an exception

else块是说如果异常没有被抛出的情况下将被执行。

4. finally块 

 

A finally clauseis always executed before leaving thetrystatement

finally块是一定会被执行的，不论异常是否产生。